Figure 9. Distribution of warm-water and cold-water organisms in the 0-100 m. layer in 

 1951. ® Warm -water organisms o Cold-water organisms. 



In the charts (Figures 1, 8, and 9), the organisms in the central areas of the Norwegian 

 Sea are shown as cold-water species, since the biotopic conditions here are similar to those of the 

 Arctic . 



In the lig^t of observations made over a number of years, we are inclined to regard them as 

 bathypelagic species as far as the Norwegian Sea is concerned. In the Norwegian Sea, these organ- 

 isms are indicators of deep waters and low temperatures . 



The heterogeneous composition of the plankton indicates the presence in the North Atlantic 

 seas of waters of different origins and confirms the existence of constant currents in the Norwegian 

 and Greenland Seas from the Atlantic Ocean and the Polar Basin. 



Thus, the plankton composition also varies with the differences in origin and distribution of. 

 the water masses. 



90 



